CVE-2022-41040: Microsoft Exchange Server Server-Side Request Forgery Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 30 Sep 2022, 3 days before the CVE record was published.

How likely is exploitation in the next 30 days?

100%

EPSS score, percentile 100 of all scored records

How severe?

8.8 High

CVSS v3.1 base score, given by the CNA

What should I do?

Required action (CISA), due 21 Oct 2022: Apply updates per vendor instructions.

Advisories and patches (1)

Which versions are affected?

Affected: 15.00.0 up to, not including, 15.00.1497.044; 15.0.0 up to, not including, 15.01.2375.037; 15.02.0 up to, not including, 15.02.0986.036; 15.02.0 up to, not including, 15.02.1118.020; 15.01.0 up to, not including, 15.01.2507.016

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 21 October 2022.

Advisories and patches

• Microsoft Exchange Server Elevation of Privilege Vulnerability (Vendor advisory)

Linked from CISA's catalog entry

• https://msrc-blog.microsoft.com/2022/09/29/customer-guidance-for-reported-zero-day-vulnerabilities-in-microsoft-exchange-server/
• https://nvd.nist.gov/vuln/detail/CVE-2022-41040

Affected products and versions

As listed in the CVE record.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Microsoft Exchange Server allows for server-side request forgery. Dubbed "ProxyNotShell," this vulnerability is chainable with CVE-2022-41082 which allows for remote code execution.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2022-41040 to its Known Exploited Vulnerabilities (KEV) catalog on 30 Sep 2022.
• CISA marks it as known to be used in ransomware campaigns.
• The due date CISA sets for the required action is 21 Oct 2022.
• The CVE record was published on 3 Oct 2022, 3 days after it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 8.8 (High), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 100% (percentile 100), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

Microsoft Exchange Server Elevation of Privilege Vulnerability

Microsoft Exchange Server Elevation of Privilege Vulnerability

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-918: Server-Side Request Forgery (SSRF)

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

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